Mouse neutrophils require BCL-XL for enhanced survival during inflammation. (A) Leukocytes from B6 mice were preconditioned in culture in the presence or absence of their respective inflammatory cytokines (i) GM-CSF or (ii) G-CSF at the indicated dose for 16 hours. Cells were then cultured in the presence or absence of 1 µM BCL-XL inhibitor (A-1331852), MCL-1 inhibitor (S63845), or BCL-2 inhibitor (ABT-199). After 16 hours, viable neutrophils (PMN) were enumerated by flow cytometry. Data are shown as mean ± SD of viable PMN per well. Data show a single representative experiment of n = 3 experiments. (B) B6 mice were injected with 10 µg LPS or PBS control IP. Sixteen hours later mice were treated with 100 mg/kg BCL-XL inhibitor or vehicle by oral gavage. After 16 hours, peritoneal cells were recovered by lavage and viable PMN enumerated by PI staining and flow cytometry. Data show a single representative experiment of 2 experiments; n = 4 animals/group; mean ± SEM . All data were analyzed using a 2-tailed Student t test. *P < .05, **P < .01, ***P < .001.